[Main characteristics of the street food sector in Bobo-Dioulasso, Burkina Faso]. / Caractéistiques de l'alimentation de rue dans la ville de Bobo-Dioulasso, Burkina Faso.

To investigate the sector of food sold in the streets of Bobo-Dioulasso and identify relevant information for action, a survey on knowledge and practices of street food vendors and consumers was conducted in June 2005. Data have been collected in 928 street food selling posts. Structured questionnaires were used to collect data from 874 street vendors and 2474 consumers. Street food sites are concentrated in places where administration and trade activities are usually running. The street food seller is a married and illiterate woman of 32 years old. Cereals (48.5%), meat (33.9%), milk (9.6%) and fruits (4.4%) are the basic consumables. The street food consumer is a non married man, 27 years old working in profit-making activity. Consumers use many criteria to choose the place to eat, at times or permanently. The street food sector represents a source of income and induces change in household eating habits. Street food in Bobo-Dioulasso needs to be better organised, by using an holistic approach that involves all the actors.

In vitro and in vivo antiplasmodial activity of 'saye', an herbal remedy used in Burkina Faso traditional medicine.

'Saye', a traditional medicine used in Burkina Faso, which consists of extracts of Cochlospermum planchonii (rhizome), Cassia alata (leaf) and Phyllanthus amarus (whole plant), showed a significant effect against Plasmodium falciparum and Plasmodium berghei parasites grown in vivo (IC(50) = 80.11 +/- 3.40 microg/mL; ED(50) = 112.78 +/- 32.32 mg/kg). In vitro the activity was lower.

Amodiaquine metabolism is impaired by common polymorphisms in CYP2C8: implications for malaria treatment in Africa.

Metabolism of the antimalarial drug amodiaquine (AQ) into its primary metabolite, N-desethylamodiaquine, is mediated by CYP2C8. We studied the frequency of CYP2C8 variants in 275 malaria-infected patients in Burkina Faso, the metabolism of AQ by CYP2C8 variants, and the impact of other drugs on AQ metabolism. The allele frequencies of CYP2C8*2 and CYP2C8*3 were 0.155 and 0.003, respectively. No evidence was seen for influence of CYP2C8 genotype on AQ efficacy or toxicity, but sample size limited these assessments. The variant most common in Africans, CYP2C8(*)2, showed defective metabolism of AQ (threefold higher K(m) and sixfold lower intrinsic clearance), and CYP2C8(*)3 had markedly decreased activity. Considering drugs likely to be coadministered with AQ, the antiretroviral drugs efavirenz, saquinavir, lopinavir, and tipranavir were potent CYP2C8 inhibitors at clinically relevant concentrations. Variable CYP2C8 activity owing to genetic variation and drug interactions may have important clinical implications for the efficacy and toxicity of AQ.

[An action research network to improve the quality of tuberculosis care in West Africa]. / Améliorer la qualité des soins aux patients tuberculeux par la recherche-action en réseau. Une expérience en Afrique de l'Ouest.

BACKGROUND: Improvement in management systems for tuberculosis (TB) care is urgently needed in West Africa. In 2003, an experimental action research network began there, involving care providers, health system managers, and TB programme managers. Each project in all 6 countries used a "patient-centered" approach to improve tuberculosis case management. METHODS: The research teams included care providers, district medical officers, anthropologists and TB programme managers. Each research team conducted its project for a one-year period and then assessed its results. The specific problems identified were low TB detection rates (Burkina Faso, Côte d'Ivoire and Niger) and poor compliance among patients receiving treatment, including their ensuing loss to follow-up (Benin, Mali and Senegal). Investigators concluded that these weaknesses were due to the lack of access to care (geographical, financial and cultural), the complexity of the care system and the low quality of care. Solutions for all 6 countries aimed at improving access to high-quality care. RESULTS: One year after the experiment began, results varied from one country to another. In general, all participants understood the need to collaborate beyond national health systems because the problems from all 6 countries were quite similar. The research process led to better sharing of work between care providers and sometimes between care providers and TB patients. It provided participants with new concepts and a constant opportunity to implement them. These repeated meetings, however, keep care providers away from their offices. CONCLUSION: The research would have improved case management and care more effectively had the teams taken into account the psychological and sociological need of TB patients. A new regional dynamic has begun and must be pursued to help improve health care systems.

Decentralising tuberculosis case management in two districts of Burkina Faso.

SETTING: In West Africa, national tuberculosis programmes (NTPs) face many problems due to the low performance of health care delivery systems and patients' social and cultural environment. OBJECTIVE: To improve the case management of TB in Burkina Faso. DESIGN: Using the operational research process as a tool, TB case management was decentralised from the district hospital to eight primary health care centres in 2003. RESULTS: Twelve months after decentralisation, the quality of case detection remained satisfactory. The delay between the identification of TB suspects with chronic cough and the confirmation of TB was reduced from 13 to 6 days. The detection rate of TB suspects during the study (30%) was twice as high as for 2001 and 2002 (15%). However, the detection rate for smear-positive TB cases decreased from 32.3% in 2001 and 2002 to 6.5% during the year of the study. CONCLUSION: Sufficient time and commitment are essential to obtain a case management system that is decentralised and effective. Efforts therefore need to continue to obtain more information and better results.

[In vivo sensitivity of Plasmodium faciparum to chloroquine and sulfadoxine pyrimethamine in the Bobo Dioulasso region (1998-2001): risk factors associated with treatments failures to the two drugs]. / Sensibilité in vivo de Plasmodium falciparum à la chloroquine et à la sulfadoxine-pyrimethamine dans la région de Bobo Dioulasso (1998-2001): étude des facteurs de risque associés aux échecs thérapeutiques de ces deux médicaments.

The therapeutic efficacy of chloroquine (CQ) and sulfadoxine-pyrimethamine (SP) was determined over a 4 year period (1998-2001) in Bobo Dioulasso, Burkina Faso, with an analysis of the risk factors associated to treatment failures to the 2 drugs. In total, 2008 children (6 months-15 years old) attending in 4 health centres (1 urban and 3 rural) were included in the study. Children were alternatively allocated to either CQ or SP The WHO 14-days in vivo field test was carried out. PCV was measured at day 0 and 14. CQ treatment failure was 24.4% (229/940), most of them being late failures. Between 1998 and 2001 a significant increase in CQ treatment failure (p < 0.001) was observed. SP showed a good efficacy with a total treatment failure of 4.4% (33/749). However; a significant increase of resistance to this drug (p=0.001) was also observed between 1998 and 2001. Among children with anaemia at day 0.85% (23/27) were no more anaemic by day 14 in the SP group, while in the CQ group the proportion was lower; 69% (27/39). However the difference between the two drugs was not significant (p > 0.1). Univariate analysis showed that the site, the age of children, the time of recruitment and the parasitaemia were significantly associated with CQ treatment failure. In the multivariate analysis these 4 variables remain significantly and independently associated with the risk of CQ treatment failure. After adjusting for the effect of the 3 other factors, the risk of treatment failure was reduced by half in rural area compared to urban area as well as in children of 5-15 years of age compared to those under 5. The risk of treatment failure was significantly increased in 2000-2001 (OR = 1.66, p < 0.05) as compared to the 2 previous years (1998-1999). It was also twice higher in children with parasitaemia > or = 16,000/microl than in those having a lower parasitaemia. For SP we have not observed such connexions with the univariate and multivariate analysis.

Evaluation of the Antiplasmodial Activity and Lethality of the Leaf Extract of Cassia alata L. (Fabaceae).

OBJECTIVE: Cassia alata L. (Fabaceae), one of the three plants contained in Saye, a polyherbal antimalarial remedy was assessed for its antimalarial potential and safety in mice. METHODOLOGY: Organic extracts were prepared from the leaves and tested on the D 10 chloroquine-sensitive strain of Plasmodium falciparum using the parasite lactate dehydrogenase assay. The 4 days suppressive test using Plasmodium berghei in mice was used to evaluate the in vivo antiplasmodial activity of the extracts. Animals were treated by oral route, once a day with 50, 100, 250 and 400 mg kg -1 b.wt., of the extracts. The acute toxicity of the extracts was assessed in mice according to Thompson and Weil method. The lethal effects of the extracts on animal's body weight, tissues, biochemical and haematological parameters were determined at 823.5, 1235.5, 1853 and 2779.5 mg kg -1 b.wt., respectively. RESULTS: The dichloromethane/methane (1:1, v/v) extract of Cassia alata was the most active against Plasmodium falciparum. The mean percent suppression of parasitemia in mice was equal to 22.5, 41.8 and 45.2% at 50, 250 and 400 mg kg -1 b.wt., respectively. No death and no clinically significant changes were recorded in mice. The maximum non-lethal dose was more than 16875 mg kg -1 in animals. No significant changes were observed in body weight, tissues morphology, biochemical and hematological parameters at doses above or equal to 2779.5 mg kg -1 b.wt. CONCLUSION: The dichloromethane/methanol leaf extract of Cassia alata had a good to moderate in vitro and in vivo antiplasmodial activity and was found to have low toxicity at high doses in tested animals.

Ten-year surveillance of drug-resistant malaria in Burkina Faso (1982-1991).

To understand the evolution of drug-resistant forms of malaria in time and in space, we carried out an analysis of the results of a series of passive and active surveys conducted in Burkina Faso between 1982 and 1991. A total of 607 tests for resistance to chloroquine and mefloquine were carried out in vitro and 3,679 tests for resistance to chloroquine, quinine, and sulfadoxine-pyrimethamine were performed in vivo. The surveys principally involved the two main cities of Burkina Faso, Ouagadougou and Bobo-Dioulasso. However, another 10 locations representing the three different zones of malaria transmission were also studied. The first cases of Plasmodium falciparum resistant to chloroquine in vitro were reported in 1983, but it was only in 1988 that in vivo resistance appeared. The first cases of in vitro resistance to mefloquine were noted in 1987 while chloroquine sensitivity at a high rate (15.8%), which decreased during the following years. The prevalence of resistance to chloroquine increased in parallel to this decrease in sensitivity to an overall peak of 41% in vitro and 16% in vivo in 1990. These rates then decreased to 3% and 6%, respectively, in 1991. This pattern of decreasing resistance was broadly similar in all sites except for the town of Bobo-Dioulasso, where the level of resistance remained stable at approximately 14% from 1988 to 1991. Only two cases of resistance in vivo to sulfadoxine-pyrimethamine were noted.(ABSTRACT TRUNCATED AT 250 WORDS)

Natural swarming behaviour of the molecular M form of Anopheles gambiae.

In Anopheles gambiae, as in most species of mosquitoes, mating is initiated in flight. The males aggregate in aerial swarms and conspecific females individually fly to these swarms where they mate with males. In this study, we investigated the swarming behaviour of A. gambiae and conducted 2 surveys in the rice field area of the Vallée du Kou in Burkina Faso in 1999 and 2002. A high number of anopheline mosquitoes were observed in this area and both molecular M and S forms of A. gambiae were found in sympatry. Swarms formed a few minutes after sunset in different places and no obvious markers were associated with their occurrence. However, swarms occurred close to cow herds generally in open flat areas, 2-3 m above the ground. Overall, 2829 anopheline mosquitoes were collected from 21 swarms composed primarily of males. A few specimens of Culex quinquefasciatus were collected from 3 swarms. Although both molecular M and S forms were found in sympatry in the village, swarms were composed almost exclusively of the molecular M form. This suggests that there are alternative swarming habits for both molecular M and S forms of A. gambiae in nature.

Malaria: use of restriction endonuclease digestion and mutation-specific PCR for antifolate resistance isolate detection.

Antifolate resistance isolates of Plasmodium falciparum in the blood of 56 patients was investigated by using PCR technology. DNA was extracted with three different methods from parasite lysate by phenol-chloroform, or from whole blood and from blood collected onto dry filter paper, by chelex-100. The expected 727-bp PCR product was obtained in all samples extracted by chelex-100, while three samples prepared by phenol-chloroform failed to show any amplified product. The crucial point mutation within the dhfr gene leading to pyrimethamine and cycloguanil resistance is localised in an Alul recognition site. Thus, the 727-bp PCR product was submitted to endonuclease digestion. Fifty out of the 56 blood samples analysed yielded the two expected restriction fragments and an undigested 727-bp band. These 50 samples likely represent mixed infection as also confirmed the specific mutation PCR. The six undigested samples amplify a 339-bp fragment using a nested PCR-specific for pyrimethamine resistance mutation. Our results show that, the rapid DNA extraction from blood using chelex-100 and the PCR endonuclease assay can be efficiently used for accurate chemosensitivity analysis in the field.

First report of a kdr mutation in Anopheles arabiensis from Burkina Faso, West Africa.

The leu-phe kdr mutation was detected in a specimen of Anopheles arabiensis during an extensive survey of pyrethroid resistance in An. gambiae s.l. in Burkina Faso. The detection of this mutation in An. arabiensis, which had so far been observed only in An. gambiae s.s., is important at both epidemiologic and fundamental levels. It can be useful to understand the history of this gene throughout the range of An. gambiae complex.

[In vitro susceptibility of 232 isolates of Plasmodium falciparum to antimalarials in Burkina Faso (West Africa)]. / Etude de la sensibilité in vitro de 232 isolats de Plasmodium falciparum aux antipaludéens au Burkina Faso (Afrique de l'Ouest).

Plasmodium falciparum in vitro susceptibility to chloroquine, quinine, mefloquine and halofantrine was investigated in patients living in Bobo-Dioulasso (Burkina Faso, West Africa). Our study was carried out from July to November 1997 at the Malaria Chemoresistance Reference Centre, Centre MurazIOCCGE. Inclusion criteria were: presence of a single infection by R falciparum with a parasite count > or =4000 infected red cells/mm3. The susceptibility to drugs was measured after an incubation period of 48 hours at 37 degrees C, under 5% CO2. (3H) Hypoxanthine was added to the medium to monitor parasite growth. 134 isolates of P. falciparum were tested against chloroquine; 24.6% (33/134) were resistant. We have also documented 11.2% (15/133) of resistant isolates to halofantrine. All the tested isolates were susceptible to quinine (n=135) and mefloquine (n=136). A significant positive correlation was found between the following IC50 values: chloroquine-quinine, quinine-mefloquine and mefloquine-halofantrine. Our study shows no significant increase of the prevalence of chloroquine-resistant strains of P. falciparum in our study area; as well as the persistence of resistance to halofantrine with regard to previous publications in the subject.

[Vaccination against malaria: initial trial with an ant-sporozoite vaccine, (NANP)3-TT (RO 40-2361) in Africa (Bobo-Dioulasso, Burkina Faso)]. / Vaccination contre le paludisme: premier essai avec un vaccin antisporozoïte, le (NANP)3-TT (RO 40-2361) en Afrique (Bobo-Dioulasso, Burkina Faso).

The vaccine (NANP)3-TT is a synthetic peptide of the circumsporozoite protein (CS) of Plasmodium falciparum coupled to tetanus toxoid (TT) as protein carrier and adsorbed to aluminium hydroxide as adjuvant. The objectives of the study were to assess the immunogenicity and the protective efficacy of the vaccine in an area where malaria is endemic. The study was conducted in a zone of irrigated rice cultivation known as the Vallée du Kou to the North of Bobo-Dioulasso. Malaria transmission is permanent in the Vallée with maxima in July and November. The study was conducted from June to December 1988. It was a controlled randomised, double blind, prospective vaccine trial. A total of 123 infants from 3 to 5 months of age were randomly assigned to three groups. Group I (controls) received three doses of TT alone, group II received two doses of TT and one of (NANP)3-TT and group III received three doses of (NANP)3-TT. These vaccines were administered simultaneously with the Enlarged Program of Immunisation (EPI) vaccines. The clinical parasitological and immunological status of the children was then monitored over a period of five months. No systemic reactions to the vaccine were observed in the infants either immediately after administration or during the follow-up. Minor local tumefactions were observed in only 3% of the children. The vaccine was found to be immunogenic with a peak IgG response at day 75, when 56% (group II) and 60% (group III) showed antibody titres of at least four times that seen at day 0. The response, however, was a short duration; by day 150 the average antibody titres were not significantly different between the three groups. The incidence and the level of parasiaemia and the incidence of clinical malaria were also not significantly different for each of the three groups during the period of the study. The association of (NANP)3 with tetanus toxoid was not shown to be immunologically inhibitive. The results, despite not showing a protective effect for the vaccine (NANP)3-TT, have shown its immunogenicity and therefore suggest that further development of this vaccine may be worthwhile.

[Preliminary study of cutaneous leishmaniasis in the town of Ouagadougou from 1996 to 1998]. / Etude préliminaire de la leishmaniose cutanée dans la ville de Ouagadougou de 1996 à 1998.

Since 1996, there have been reports of cases of cutaneous leishmaniasis in the town of Ouagadougou. The incidence has been on the rise but precise figures are not known. The object of the present study has been, first, to record cases of cutaneous leishmaniasis having occurred in private and public health centres in Ouagadougou from 1996 to 1998 and, second, to determine the progression of the disease in space and time. We wished also to confirm clinical cases in 1998 by parasitological examination, identify different clinical forms of the disease and map out cases in the town. We carried out a retrospective study from 1996 to 1998 and a prospective study in 1998. All cases recorded in this period in visited health centres were included. A total of 1845 cases of cutaneous leishmaniasis was identified, 50.3% of whom concerned women. The age of patients varied between 1 and 79 years for 356 patients, with a mean age of 26.7 years. Cases increased between 1996 and 1998 (1996 = 61 cases, 1997 = 552 cases, 1998 = 1218 cases). The months of highest incidence were August (13%), September (15%) and October (17%). Peripheral districts (28, 30, 29, 16, 15) in south-eastern areas of the town were the worst touched with 87% of cases. On average, patients seek care after 2 months of progression of the disease. The ulcero-crusted form (68.2%) was the most frequent clinical form observed for 327 patients, but almost half of the cases had more than one site of infection, (43.5%). Over half of the patients presented fewer than 10 lesions with an average of 6. The most common locations were on uncovered parts of the body, notably the superior (53%) and inferior limbs (49%). The parasite could be tested for by smear on 52 patients only in 1998 and 53.8% of cases tested were positive. Leishmania major, which is very prevalent in West Africa was identified in one patient. The vectors and main reservoirs of the parasite were not studied. Case management was generally incomplete; the most commonly prescribed drugs were antibiotics (70% of patients), but self-medication was frequent. Our recommendations after this preliminary study are: undertake multidisciplinary studies on cutaneous leishmaniasis in Ouagadougou in order to understand the local aetiology (vectors responsible for transmission, rodent and domestic animals involved in the epidemiological chain, parasite species); identify all other areas in the country where the disease is highly prevalent provide health care staff with a decisional algorithm and protocol therapy carry out and active control programme for cutaneous leishmaniasis in Burkina Faso.

[Filarial multiparasitism in the savannah zone in Burkina Faso]. / Etude du polyparasitisme filarien en zone de savane au Burkina Faso.

From june 1985 to may 1986, 1.209 consulting patients were examined for filariae in skin and blood. Among patients with microfilariae 17% had associations of filarial infections. The multiple infections rate seemed more important in man than woman and increased with age. The results showed that associations were not due to chance only. The frequencies of associations between Dipetalonema perstans and Onchocerca volvulus at one hand, Dipetalonema perstans and Wuchereria bancrofti on the other hand were highly significant. Symptoms of filarial associations were studied and subsequent therapeutic attitude discussed.

[Preliminary epidemiological study of dracunculosis in the southwest of Burkina Faso]. / Etude épidémiologique préliminaire de la dracunculose au sud-ouest du Burkina Faso.

An epidemiologic survey was carried out before the setting up of an applied research project on dracunculiasis control through three strategies. The data were collected by house-to-house visits and from family cards. The overall incidence rate was 10.3 per cent + 0.9 with variations from 1.7 to 35 per cent according to the villages. The incidence rates were significantly higher in the 5-14 and 15-59 years age groups. On the opposite, there was no significant difference between the rates according to sex. The disease presented a family feature and cases were concentrated in 35 per cent of families. The proportion of polyparasitism was important more than half of patients had two or more worms. The measurement of the same indicators at the end of project will allow the assessment of the project results.

[Dracunculosis control by three techniques in the south-west of Burkina Faso. Compared efficacy of the techniques]. / Contrôle de la dracunculose par trois techniques au Sud-Ouest du Burkina Faso. Efficacité comparée des techniques.

A study on the effectiveness of health education, chemical treatment of water sources and the two combined measures was carried out in ten dracunculiasis endemic villages in South-Western Burkina Faso from 1985 to 1989. Data on cases were collected by active case-finding. Dracunculiasis was eliminated from four villages through health education and from four other through combined measures after four years. Endemy was reduced by 67 p. 100 in two villages through chemical treatment. Difficulties encountered in the setting up of the measures and place of each of them in control programs are discussed.

[Malaria morbidity in adults living in urban Burkina Faso]. / Morbidité palustre, notamment chez l'adulte, en milieu urbain au Burkina Faso.

Urbanization in countries located in areas of endemic malaria can decrease the level of immunization and make malaria a more serious public health problem in adults. The purpose of this prospective study was to describe the clinical and parasitological features of malaria in adults in the city of Bobo Dioulasso in Burkina Faso. Study was carried out between July and November 1992 at the medical testing laboratory of the Muraz Center in 494 patients including 378 adults and 116 children under the age of 15 years. The parasitic index was 23% in adults as compared to 62% in children. There was not a significant difference in the parasitic index according to whether the place of residence was located in the city center or outlying suburbs. Parasite density ranged from 6 to 145,000 parasites per mm3 in adults as compared to 6 to 426,000 parasites per mm3 in children. Median parasitemia was 696 parasites per mm3 in adults as compared to 8800 per mm3 in children. The threshold of parasitemia for appearance of clinical symptoms was thus lower in adults than in children. Because of the poor positive predictive value of the main clinical features and the high incidence of self-treatment, microscopic examination is indispensable to confirm diagnosis of malaria. The results of this study indicate that urbanization in the city of Bobo Dioulasso has not significantly changed the level of immunization to malaria in adults.

[Variation of the parasite density of Plasmodium falciparum in asymptomatic carriers: consequences for malaria chemoresistance studies]. / Variation de la densité parasitaire de Plasmodium falciparum chez des porteurs asymptomatiques: conséquences dans les études de chimiorésistance du paludisme.

During the studies on malaria chemoresistance, we noted great variations in parasite density of Plasmodium falciparum between screening in the morning and final selection in the afternoon, in asymptomatic people. To better understand this phenomenon, we conducted a study in october 1987 on primary school children in a village near the city of Bobo-Dioulasso, at the peak malaria prevalence. We performed 3 blood-smears at 8 a.m., 2 p.m. and 8 p.m., on Day 0 and Day 4, to an initial number of 86 children, aged from 6 to 9 years. By the end of the study 44 children remained who fulfilled the inclusion criteria Among them 35 showed a parasitaemia on Day 0 and 9 remained negative. On Day 4, 28 were positive and 16 remained negative. Of the 35 children positive at entry to the study 16 remained continuously positive, the others were negative on at least one occasion. Of the 28 children positive on Day 4, 14 remained continuously positive. For the 16 people with a parasitaemia continuously positive on Day 0.7 (43.7 p. cent) became spontaneously negative on Day 4. But considering the small size of our sample, the analysis of the nycthemeral variation and of the variation between the two days did not show a significant difference. Further studies involving a greater number of blood-smears during a longer period and concerning more people, should be conducted. The possibility of spontaneous negativation of the parasitaemia without drug absorption shows that there are some cases of false malaria chemosensitivity that are declared when the in vivo tests are not coupled with in vitro tests.

[The simplified isotopic microtest: a method for studying the drug resistance in vitro of Plasmodium falciparum to antimalarial drugs]. / Le microtest isotopique simplifié: une méthode pour l'étude de la chimio-résistance in vitro de Plasmodium falciparum aux antipaludiques.

We evaluated the efficiency of the simplified version of the isotopic microtest (simplified test) and compared it to that of the complete version (standard test), for determining the susceptibility of local strains of Plasmodium falciparum to chloroquine, quinine, mefloquine and halofantrine. The study was carried out from July to November 1996, at the MURAZ Center, Bobo-Dioulasso, Burkina Faso. The inclusion criteria were: single infection with P. falciparum, with a parasite count of at least 4,000 infected red blood cells per mm3. Susceptibility to each drug was determined after incubation for 48 hours at 37